Retractable corner unit for inner form sections



Jan. 23, 1951 R. G. LE TOURNEAU 2,538,970

RETRACTABLE CORNER UNIT FOR INNER FORM SECTIONS Filed April 19, 1948 2Sheets-Sheet l 12 10 x 17 14 l i I 8 1e v 15 3a .J 6

f n 11 3 I] INVENTOR .61 e j 35 R L Earneaw I ATTORNEYS RETRACTABLECORNER UNIT FOR INNER FORM SECTIONS Filed April 19, 1948 Jan. 23, 1951R. G. LE TOURNEAU 2 Sheets-Sheet 2 INVENTOR R. G. lej'c'aurneau Mi muli/ATTORNEYS Patented Jan. 23, 1951 RETRACTABLE CORNER UNIT FOR INNER FOR-MSECTIONS Robert G. Le Tourneau, Longview, Tern, assignor to R. G. LeTourneau, Inc., Stockton, Oaliii, a corporation of CaliforniaApplication April 19, 1948, Serial No. 21,805

3 Claims.

This invention is directed to improvements in an inner form section of aform assembly adapted for use in the construction of monolithic concretehouses or the like; the invention relating particularly to an inner formsection of the type shown and described in copending U. S. patentapplication, Serial No. 740,046, filed April 8, 1947, now U. S. Patent2,524,981,

Such inner form section includes a horizontal roof plate, and separatevertical walls; the latter being movable inwardly or retractible from anormally advanced working position, whereby to free the cast structurefrom said inner form section.

The upper horizontal edge portions of the form section are of bevelconfiguration and comprise cooperating cove plates along adjacent edgesof the roof plate and walls; it therefore being advantageous to providespecial upper corner structures to permit the walls to be retractedwithout interference.

These upper corner structures or units are the subject of the presentinvention; one object being to provide a unit, for each upper corner,which is normally fixed in advanced working position to provide a cornerform, but is readily retractible to thereafter permit the walls andcorresponding cove plates to likewise be retracted.

Another object of the invention is to provide an upper corner unit, forinner form sections, which permits of contraction of the latter withoutdamage to the cast structure at said upper corners.

A further object is to provide an upper corner unit, for inner formsections, which produces, in the cast structure upper corners whoseinner surface appearance is quite attractive.

An additional object of the invention is to provide an upper cornerunit, for the purpose described, which is characterized by simplicity ofstructure and economy of manufacture; inner form sections embodying theinvention being manipulated more readily than otherwise.

A further object of the invention is to provide a practical and reliableupper corner unit for inner form sections which will be exceedinglyefiective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relativearrangement of parts as Will fully appear by a perusal of the followingspecification and claims.

In the-drawings:

Fig. 1 is a perspective view of one of the retractible upper cornerunits as embodied in an inner form section; said upper corner unit beingin its advanced, working position.

Fig. 2 is an enlarged fragmentary plan view of one of sa d uppercorner'units in advanced working position; the roof plate of the innerform section being removed,

Fig. 3 is a similar view, but shows said upper corner unit in retractedposition.

Fig. 4 is an enlarged fragmentary sectional elevation of the inner formsection showing one of the upper corner units in side elevationfsaidunit being in advanced working position in. full lines, and inretracted, non-worl-zing position in dotted lines.

Referring now more particularly to the charactors of reference on thedrawings, the retractible upper corner unit is here illustrated asembodied in an inner form section, for monolithic concrete structures,which includes a plurality of vertical walls l disposed at right anglesto each other, and a horizontal roof plate 2.

The upper horizontal edge portions of the inner form section are ofgenerally beveled configuration and comprise longitudinal cove plates 3afiixed to the upper edges of the walls Land extending at an upward andinward incline. Upper longitudinal cove plates i are affixed to thecorresponding edges of the roof plate 2 and extend therefrom at adownward and outward slope, lapping in relatively slidable relationlongitudinal lips 3a along the upper edges of said cove plates 3.

The upper longitudinal cove plates 4 extend fully to each corner of theinner form section and are there secured together, as at 5. However, thelower longitudinal cove plates 3 terminate short of each corner of theinner form section, as at 6, whereby to provide a corner opening I.

Below the corner opening '4 the inner form sec tion includes, at eachcorner, a g-eneraiy diagonal corner plate assembly which comprisesccoperating vertical corner plates 8. The corner plates 8, whileextending generally diagonally of the corresponding corner, proiect fromadjacent edges of the vertical walls 5 in slightly outwardly convergingre ation to a lapping separable joint 9. The corner plates 8,cooperating as described, terminate at their upper end in the samehorizontal plane as the upper edges of the walls i;

The walls I are normally advanced, as shown, for use of the inner formsection, but said walls are retractible inwardly by mechanism not hereshown, for the purpose of freeing said wals from a structure previouslycast thereabout. The cooperating corner plates 8, being vertical andlapping as shown, permit of such inward retraction of the side walls Iwithout interference. However, this would not be true if the lowerlongitudinal cove plates 3 were in abutment at adja" cent ends, and forthis reason it is reouisite that special upper corner units be provided.These units comprise the essence of the present invention, and as eachis a duplicate of others, a showing and description of one issufiicient.

The numeral it indicates a corner plate unit formed to symmetrically andmatchingly engage in the corner opening I from the rear, in the mannershown in Fig. 1.; such corner plate unit including a plurality of platesections welded together in predetermined angular configuration.

The corner plate unit I9 is maintained in its normal advanced workingposition in the corner opening I, and flush with the adjacent partsofthe inner form section, by means of inwardly ofiset stop flanges l lwhich extend from the side and upper edges of said plate unit inunderlying relation to adjacent edge portions of the lower longitudinalcove plates 3 and the upper longitudinal cove plates 4.

The corner plate unit I?) is mounted for retracting motion in a planegenerally diagonal of the corner opening I by the following structuralarrangement:

An upstanding swing bar 52 is affixed, at its lower end, to a mountingplate [3, in turn secured to the vertical frame structure Id of one ofthe walls I.

The upstanding swing bar [2 is attached, at its lower end, by a pivotbolt I5, to the mounting plate [3, said bar and plate being disposed sothat the bar is. swingable in a plane to accompl'ish the aforesaidretraction of. the corner plate unit it; the latter being afiixed, as bywelding, to the upper end of said bar.

In order to normally maintain the corner plate unit It? in its advancedworking position, the

mounting plate is is fitted with a retaining strap [.6 which spans theupstanding swing bar l2 and is of a length to form an elongated guideslot H for such. bar.

The strap 16 thus guides the upstanding swing bar 12, and to normallymaintain the latter in position with the corner plate unit H) a holdingwedge 18 is driven into the slot ['5' between the rear edge of the barI2 and the rear end of the retaining strap l6;

To retract the corner plate unit IE3, the holding wedge I8 is firstdriven out, and then a pull eement, such as a hook, is engaged with aperforated ear t9 on the upper end of said bar, the

latter then being pulled rearwardly, carrying the corner plate unit !9therewith to its retracted position shown in dotted lines in Fig. 4.

When all of the upper corner units have thus been retracted, the Walls Imay be pulled inwardly without interference to clear them from the castmonolithic concrete structure which surrounds the inner form section.

To return the upper corner units to working position requires the simplemanual operation of. replacing and redriving the corresponding holdingwedges [8.

From the foregoing description it will be readily seen that there hasbeen produced such a device as substantially fulfills the objects of theinvention as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of the device, still in practice such deviations from suchdetail may be resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new anduseful, and upon which Letters Patent are desiredi 1. An upper cornerunit for an inner form section having an upper corner opening therein,comprising an initially separate plate unit adapted to engage in saidcorner opening from within the section, an upstanding swing armpivotally mountedwithin the section, the plat'eunit being mounted on theswing arm and the latter being swingable in a path to retract the plateunit into the section from said engaged position in the opening, andmeans to releasably lock the swing arm against swinging; said meansincluding a structure provided with a guide slot through which the armextends in swingable relation, and a wedge adapted to be driven into theslot between one end thereof and the arm.

2. An upper corner unit for an inner form section which includes a roofplate, retractible walls in angular relation to each other approachingthe vertical corners of the section, generally diagonal vertical cornerassemblies extending in separable relation between adjacent verticaledges of the walls, and generally beveled horizontal cove assembliesextending in separable relation between adjacent edges of the walls androof plate, the corresponding vertical corner as semblies and a part atleast of the horizontal cove assemblies terminating short of each otherto form upper corner openings in the sections; comprising a corner plateunit symmetrical to said opening adapted to matchingly engage in thesame from within the section, an upstanding swing arm pivotally mountedwithin the section, the plate unit being mounted on the swing arm andthe latter being swingable in a path to retract the plate unit into thesection from said engaged position in the opening, and means toreleasably lock the swing arm against swinging; said means including astructure provided with a guide slot through which the arm extends inswingable relation, and a Wedge adapted to be driven into the slotbetween one end thereof and the arm.

3. In combination: vertically disposed side wall plates disposed atsubstantially right angles to each other, adjacent vertical edges ofsaid side wall plates being spaced apart in a plane diagonal to suchedges, a vertical corner plate on each of the adjacent edges of the wallplates, said corner plates projecting diagonally toward each other andlapping, an upwardly and inwardly sloping cove plate. on the upper edgeof each wall plate, a substantially rectangular roof plate, a downwardlyand outwardly slopin cove plate on each edge of the roof plate, thelower edges of such last named cove plates lapping the upper edges ofthe first named cove plates, such assembly of plates providing an uppercorner opening defined by the top edges of the corner plates, theadjacent ends of the first named cove plates and the lower edges of thesecond named cove plates, a separate corner plate unit matchingly fittedinto said upper corner opening to close the same, a vertically disposedswing bar fixed to and depending from the under side of said cornerplate unit, the lower end of said bar being pivotally supportedoutwardly from one of the corner plates, and means to releasably holdsaid bar in vertical position.

' ROBERT G. LE TOURNEAU.

REFERENCES CITEE) The following references are of record n the file ofthis patent: 7 UNITED STATES PATENTS

